ST Fiber Optic Jumper Cables‎ is still the most popular pigtail, this ST Fiber Optic Jumper Cables‎ has a bayonet mount and a long cylindrical 2.5 mm ceramic (usually) or polymer ferrule to hold the fiber. Clearly speaking, The ST fiber pigtail (Straight Tip) is a fiber pigtail which uses a plug and socket which is locked in place with a half-twist bayonet lock. The ST Fiber Optic Jumper Cables‎ was the first defactor standard for fiber optic cabling and ST fiber pigtail is one of the leading fiber pigtails.The Telecomposer ST pigtail has a bayonet-style housing and a long spring-loaded ferrule hold the fiber. They are available in both multimode or single mode versions. Horizontally mounted simplex and duplex adapters are available with metal or plastic housing, with a choice of phosphor bronze or zirconia split sleeve. Telecomposer also offers the epoxy-free ST XPFit pigtail for quick field termination. The ST is one of the older generations of Fiber Optic Jumper Cables‎, but is still widely used for multimode networks, including LANs for buildings and campuses.